Action Points

Young people - especially young African Americans - appear to have the highest lifetime risk for developing end-stage kidney disease (ESRD) following kidney donation, according to an online risk-prediction model designed to quantify overall risk before donation.

Note that healthy older people were projected to have a relatively low lifetime risk for ESRD, even when they had high blood pressure or other conditions widely considered to be contraindications for kidney donation.

Young people -- especially young African Americans -- appear to have the highest lifetime risk for developing end-stage kidney disease (ESRD) following kidney donation, according to an online risk-prediction model designed to quantify overall risk before donation.

The 15-year observed risk for developing ESRD following kidney donation in the United States was 3.5 to 5.3 times as high as the projected risk for non-donors, with the highest risks projected to be among middle-aged black men, younger African Americans, and younger people of all ethnicities.

Healthy older people were projected to have a relatively low lifetime risk for ESRD, even when they had high blood pressure or other conditions widely considered to be contraindications for kidney donation, researcher Morgan Grams, MD, PhD, of Baltimore's Johns Hopkins Bloomberg School of Public Health, and colleagues, wrote in the New England Journal of Medicine, published online Nov. 6.

In a written statement, Jennifer Martin, the National Kidney Foundation's vice president for constituent services, called the risk prediction calculator "an innovative tool to help improve safety for those considering living kidney donation."

"Living kidney donation is generally considered safe in healthy people. However, there are some risks that potential donors need to consider carefully, including a somewhat higher long-term risk of end-stage renal disease in certain individuals," she wrote.

"While pre-donation screenings do an excellent job determining the health and well-being of potential kidney donors, this tool provides a valuable, unbiased way to assess the long-term health prospects of these individuals. Using this tool in conjunction with a transplant center's pre-donation screening process will improve donor safety and help streamline the donor selection process."

Kidney Donation Rare Among Older Patients

Older patients are often considered poor candidates for kidney donation, especially if they have these conditions, but Grams told MedPage Today that the practice of rejecting older donor candidates based on age alone appears unwarranted.

"There has been no empirical framework by which to accept donors, and hopefully this provides that framework," Grams said. "It may be appropriate to be a little more cautious when considering young people as candidates, and, conversely, perhaps we are rejecting older donors when we shouldn't be."

Around 30,000 kidney transplants involving living donors occur worldwide each year, and in the absence of formal assessment criteria for assessing long-term risk, standards for determining who is and is not an appropriate candidate for kidney donation vary widely among transplant centers, according to the researchers.

"Controversy exists over whether donor candidates with certain health characteristics, such as older age or hypertension, should be accepted for kidney donation," they wrote. "Some transplantation centers use more stringent criteria for younger donors than for middle-aged donors, given the long post-donation life expectancy during which complications may develop."

The researchers used risk associations from a meta-analysis of seven general population cohorts assessing long-term kidney failure risk, "calibrated to the population-level incidence of ESRD and mortality in the United States," to project the estimated long-term incidence of ESRD without kidney donation based on the 10 characteristics.

They then compared 15-year projections with the observed actual risk among 52,998 living kidney donors in the U.S.

The seven cohorts included close to 5 million participants followed for up to 16 years. The 15-year projection of ESRD risk for the average kidney-donor candidate varied according to age, sex, and race, with the highest risk seen among middle-aged black males.

"For a 20-year-old base-case candidate, the 15-year projected risk was 0.08% among black men, 0.05% among black women, 0.02% among white men, and 0.01% among white women," the researchers wrote. "The corresponding estimates for a 40-year-old base-case candidate were 0.24%, 0.15%, 0.06%, and 0.04%; for a 60-year-old base-case candidate, the estimates were 0.32%, 0.18%, 0.13%, and 0.08%, respectively. As expected, the model-based lifetime projections were generally higher than the 15-year projections, especially among younger persons, although the risks were less than 2% for all base-case scenarios."

The researchers concluded that the online risk tool should lead to more uniformity among transplant centers assessing kidney donor eligibility, while enhancing informed consent and shared decision making with donor candidates.

"Our ultimate goal is to develop a tool where we can sit down with a potential kidney donor and say, 'This is your risk if you don't donate, and this would be your risk if you do donate, so you can decide if you feel the risk is too high,'" Johns Hopkins transplant surgeon and study co-author Dorry Segev, MD, PhD, noted in a written press statement.

The research was supported by grants from the NIDDK and the National Kidney Foundation.

Lead researcher Morgan Grams, reported no relevant relationships with industry.

Reviewed by Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, BSN, RN, Nurse Planner

More in Nephrology

MedPageToday is a trusted and reliable source for clinical and policy coverage that directly affects the lives and practices of health care professionals.

Physicians and other healthcare professionals may also receive Continuing Medical Education (CME) and Continuing Education (CE) credits at no cost for participating in MedPage Today-hosted educational activities.